Generally speaking, electronic displays are used to present information visually in various contemporary information processing systems. Interactive “touchscreen” displays may combine graphical user interface (GUI) and/or other input functionality with the visual presentation of the information.
Some of the information processing systems with which touchscreens are used may be operable for processing critical data, for which transactional reliability and security become significant factors. For example, the success of an operation may rely on related “mission critical” data processing.
The field of avionics relates to the electronic systems of aircraft, spacecraft, and satellites. While critical data are significant in the context of many contemporary business operations, avionics presents a clear and high example of the significance of reliable and secure processing of critical information. In the context of avionics, the costs of failure in relation to information processing may be unacceptably high.
Moreover, critical data may have a high time value, low duration of fresh relevance, and related heightened levels of urgency, e.g., to pilots and other aviators. A timely user response may be appropriate upon receipt of such critical information. In use environments like the cockpits and flight decks of aircraft, displays may present the information under high levels of ambient illumination or other suboptimal situational or environmental conditions. The reception of the information however may depend, at least in part, on the ability of pilots and other users to perceive the data presented and thus, the viewability with which it is presented.
Displays used in avionics and some other applications may be designed to present critical information effectively, which comprises satisfactory high levels of visibility and viewability. As used herein, the term “visibility” may refer to objective attributes related to visibility, clarity, and legibility, and the term “viewability” may refer to somewhat more subjective factors relating to perceptual and/or psychological attraction of the visual attention of users to particular visible portions of a display.
To sustain high visibility and viewability, displays used in avionics and some other applications may comprise specified optical performance criteria. For example, avionics displays may be designed to feature high luminance (intensity) and contrast (dynamic range) capabilities, as well as reflectance characteristics, which may relate to low values of specularity and diffuseness.
Touchscreen displays however may exhibit diminished optical performance over certain viewing areas that sustain heightened levels of tactile interaction. Tactile interaction may be associated with haptic user inputs. The tactile interaction levels may be considered heightened in relation to other areas of the display, which may have significantly lower levels of tactile interaction.
The diminished optical performance in the certain touchscreen display areas may relate to contamination and wear associated with repeated physical touching of the front surface of the display, and the types of tactile contact that the areas may sustain. Relative to the less-frequently touched regions of the touchscreen display surface, the more frequently touched surface areas or those that sustain certain kinds of touches may become optically fouled or marred. Optical performance may be degraded or diminished, e.g., by contamination such as fingerprints, dirt and dust, smudges, smears, oily materials (including e.g., oils, greases, and waxes), smoke and other colloidal materials or other contaminants. The optical performance may also be diminished by wear or damage, such as scratches, thinning, or patches of comparative roughness and, e.g., the degradation of display surface reflectance characteristics associated therewith.
Some approaches to preserving the effectiveness with which critical information is presented may be more simplistic than practical or consistently reliable. For example, an approach to removing the contaminants accumulated over the viewing surface of a touchscreen display (or dealing with wear) may relate simply to cleaning (or repairing or replacing) the display as-needed and/or according to a planned maintenance schedule. Approaches to using the display in bright ambient lighting may relate simply to moving the display translationally to an area of lower ambient illumination, rotating its viewing surface away from a source of bright and/or direct lighting, or physically shading the viewing surface therefrom. However, these approaches may not be feasible or practicable in some of the settings in which the touchscreen displays are deployed and used.
For example, avionics touchscreen displays deployed and used in an aircraft cockpit or flight deck may be disposed in a stationary, rigid, or immobile position relative to a control console in which they may be mounted. The confines of the cockpit may also deter an operator's ability to shade the viewing surface of the display. Moreover, it may be impractical (perhaps even unsafe, under some conditions) to clean the display surface of (or repair/replace) a touchscreen display during its use, e.g., during some flight operations. Additionally, even if cleaning (or repair/replacement) of a touchscreen display may be feasible in some situations, critical information presented therewith may be obstructed or occluded while the cleaning takes place, or touches and touch related actions (e.g., wiping) associated with the cleaning may cause inadvertent and/or erroneous inputs to haptic surfaces.
Therefore, a need exists for presenting critical information effectively under various ambient lighting conditions on an interactive display, which is also operable for receiving user inputs. A need also exists to present the critical information effectively with high levels of ambient illumination on an interactive display that precludes or obviates changing the position thereof over a translational axis and/or a rotational axis, or shading a viewing surface thereof from bright and/or direct lighting sources. Further, a need exists to preserve or sustain the optical performance of an interactive display, and the viewability of critical information presented on the viewing surface thereof, without cleaning or wiping the viewing surface, at least during the presentation of critical information therewith.